Done with this game

So ive beat the game got no achievements for it or anything ive done, i deleted the game and my account of my xbox and redownloaded the game and my account back on and beat the game again and still nothing for that or the kills ive got, im level 44 and no achievements for ranks either, i give up. This is obviously not going to be fixed, i have achievements for last 3 missons so not sure how if cant get first ones?! My gamerscore is only 200 for the game when should be alot more